The invention relates to a breechblock for barrel weapons, having a breechblock head which is guided in a breechblock guide and, by means of a control element which can be moved to and fro in a straight line and has control ramps, can be brought out of a loading position into a locking position, which is parallel to and axially displaced with respect to the loading position, inside a breechblock bearing, which breechblock head has supporting surfaces, which are associated in a form-locking manner with the control ramps of the control element, and at least one locking boss, which corresponds with a recess in the breechblock, for the purpose of locking in the locking position, as represented in U.S. Pat. No. 3,044,203 A, for example.
The breechblock head is there surrounded by a slide, which is held by way of guide lugs and a bolt carriage, the extensions of which are led in a straight line by way of slits in the side walls of the bolt housing. In order to be able axially to lift the breechblock head during the rectilinear movement which is initiated by way of a stem, there are provided in the breechblock head inclined grooves, with which corresponding projections of the stem cooperate. Furthermore, the breechblock head has a locking boss with an inclined surface, which locking boss can engage in a recess in the bolt housing when the breechblock head takes up the locking position.
Such a bolt is constructed so as to be relatively long and in addition to a breechblock head of complicated construction requires a slide which is likewise of complicated construction and a bolt carriage, all of which are to be guided in the bolt housing.
A further disadvantage of this breechblock is to be seen in that because of the locking surface which is only on the upper side, it makes it difficult to transfer the overturning moment, which occurs during the development of the shot, via the slide to the bolt carriage, something which requires the components to have a fit with close tolerances.
According to a subsequently published proposal, the breechblock head of such a breechblock with recesses in the breechblock bearing has corresponding locking bosses and is provided with control pins which cooperate with control ramps of a control plate which can be moved in a straight line, in order to be able to bring the breechblock head out of the loading position into the locking position; see DE 197 34 042 A1.
Many other breechblocks which render possible the loading and sealing closure of the rear barrel end after the barrel weapon has been loaded are also known. The most usual are, in the case of hand firearms, so-called rotating boss breechblocks, in which by means of a manual downwards movement, at right angles to the weapon axis, of a bolt handle, a locking boss is rotated into a recess of the barrel or the breech casing for locking; see U.S. Pat. No. 2,649,800 A.